Question

(-3,117)(0,45)(3,27) please help ASAP quadratic regression

Answer 1

y = 3x² -15x +45

Explanation:

Your friendly graphing calculator can tell you the coefficients of a quadratic regression function fitting these points. That function is ...

y = 3x² -15x +45

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The charting function of a spreadsheet can add a polynomial "trend line" to the chart for you. This is shown in the second attachment.

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If you want to find the quadratic coefficients by hand, you can use the given points in the equation ...

ax² +bx +c = y

to get three equations in three unknowns. The corresponding augmented matrix is ...

`\left[\begin{array}ccc9&-3&1&117\\0&0&1&45\\9&3&1&27\end{array}\right]`

Its solution is (a, b, c) = (3, -15, 45), in agreement with the other two solutions.